| Name | Company Number | Date Appointed | Rating |
|---|
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| GEOSCAN LIMITED | 02301350 | 08/01/1992 | 24/03/2009 | Dissolved |
| SPECTRUM DATAGRAPHIC SYSTEMS INTERNATIONAL LIMITED | 02046024 | 24/11/1991 | 24/03/2009 | Dissolved |
| SPECTRUM ENERGY AND INFORMATION TECHNOLOGY LIMITED | 06266892 | 01/06/2007 | 24/03/2009 | Dissolved |
| SPECTRUM GEOPHYSICAL SERVICES LIMITED | 01309396 | 10/11/1991 | 24/03/2009 | Dissolved |
| SPECTRUM INFORMATION TECHNOLOGY LIMITED | 01588885 | 10/11/1991 | 28/07/2014 | Dissolved |
| SPECTRUM RESOURCES LIMITED | 02236114 | 27/11/1990 | 24/03/2009 | Dissolved |
| SPECTRUMITECH LIMITED | 04391906 | 19/03/2002 | 24/03/2009 | Bronze |